The most ambitious mug-shot blogs present themselves as hybrids of newspaper and fetish sites, with photos organized under section titles that range from “Local News” and “Sports” to “Transgender” and “Beat-Up.” (Some news sites have themselves appropriated the form. The CBS-affiliated, WTSP Channel 10 news, “Tampa Bay’s news leader,” runs a slide show called “Notorious Women” on its Web site, which features dozens of mug shots of attractive women. The entertainment potential of mug shots has crept back to the source: a sheriff’s department in Arizona invites users to its Web site to vote on the “mug shot of the day.”) These sites are full of pathos and picturesque weirdness: little old ladies, suspects whose uncooperative heads are propped up by anonymous gloved hands, characters whose masklike expressiveness seems more appropriate to commedia dell’arte, people done up in elaborate Halloween costumes of animals or devils (or, fatefully, of prison inmates), a mild-mannered looking man with a “FUCK YOU” tattoo covering his entire forehead.

Mug-shot sites brand themselves as a public service, and offer the requisite disclaimers that everyone pictured on them is innocent until proven guilty. But, of course, mug shots are the very image of guilt, and seem almost proof of it, which is why some states caution judges and prosecutors against submitting them to juries. And it’s for this precise reason—instant lurid appeal—that mug-shot blogs can be profitable. Some, like arrests.org and mugshots.com, run ads from major brands: Southwest Airlines, Zipcar, Adobe, Lysol, Nokia. Mugshots.com partners with ten separate vendors with names like mugshotbusters.com that provide a service for people desperate to have their mug shot removed from the site. This semi-extortion scheme is apparently legal.

In case there’s any doubt about the relationship between these sites and online social networks, mug-shot profiles are furnished with a Twitter button. Users can click directly through a particular mug shot to find the person on Facebook. This gets at these sites’ unspoken service as a cultural corrective to the endless self-presentation that happens on social-network sites: here we are allowed to see, or to imagine, what our friends and neighbors look like when they aren’t reclining on the beach or looking good at parties. Mug shots are the gargoyles crouching at the ledges of the cathedral of Facebook.